Improvement in making steel castings



(33) WHLLIAM KELLY.

Improvement inmaking Steel Castings.

N0. 122,255. Patented Dec. 26,1871.

GFFICE.

maar-.

WILLIAM KELLY, OF LOUISVILLE, KENTUCKY.

IMPROVEMENT IN MAKING STEEL CASTINGS.

Specification forming part of Letters Patent No. 122,255, dated December26, 187

SPECIFICATION.

To all whom it may concern:

Be it known that I, WILLIAM KELLY, of Louisville, in the county ofJefferson and State of Kentucky, have invented certain new and usefulImprovements in Process of Making Steel Castings; and I do herebydeclare that the following is a full and exactdescription thereof,reference being had to the accompanying drawing making a part of thisapplication.

' My invention consists in the process and apparatus for molding steel,by which the dificulties heretofore experienced of making sound castingsare overcome, as will be hereinafterv more fully set forth.

In pouring fluid steel into a mold the intense heat contained in thesame produces vaporization of small particles, and the inability of thisvapor to escape produces small holes, or honeycombs77 as they aresometimes called, which of course render the casting more or less weakand otherwise objectionable. Many attempts `have been made to overcomethis difficulty, but with ill success. The most important has `been theemployment of copper molds, the great conducting power of the copperserving to convey the heat away so rapidly as to prevent thevaporization and consequent formation of honey-comb 5 but this curebrings with it-an objection in another direction, namely, that where thecasting is at all intricate or has any inequalities 0f form varyingmaterially from a smooth surface the l copper mold, being rigid andinflexible, the rapid cooling and contraction of the steel will cause itto crack, so that for very many forms of castings copper molds cannot beconstructed so as to relieve the castings quick enough to preventcracking; and, again, where the casting is designed to have thin edges,these thin vedges are liable .to be defective from wants or spaces inthe mold not filled up with steel. The metallic mold is alsoobjectionable on account of the difdculty of freeing the castings fromthe same. To remedy these objections is the object of my `invention; andto enable those skilled in the art to more fully understand the same Iwill proceed to describe the process and apparatus used by me, referringby letters to the accompanying drawing, in which- Figure l is a top viewof a mold ready to re- Fig. 2 is a vertical cross-section at the line a:w, Fig. l; and Fig. 3 is an end view looking from the left at Fig. 1.

Similar letters indicate like parts in the several figures.

A is an iron frame or ask, intended to contain either dry or greenmolding-sand, though I prefer dry. B B indicate the molds for twoplowpoints made therein. The lines C C are the out.

lines of the two cope-s or covers of copper, of a shape correspondingwith' and adapted to fit over and close -the molds; and the heavy dottedlines of D D represent pieces of copper embedded in the sand, so as toact as a facing to thatthe point l of the ilask resting on the point 2of the door-frame, and as soon as lled it is turned back to the positionshown at Fig. 3 to cool. G is a clamping-bar for holding the copes7 orcovers C C in place by means of two thumb or set screws, c c. Theconstruction of this clamp-bar is clearly shown at Fig. 2. The end tothe left is turned down at right angles, as seen at d, `and is slightlycut away, or shoulders formed thereon, at 3 to lock it with an openstaple, e, one ofwhich is secured or cast upon either end of the iiask.Another end piece, f, independent of the bar G and similar to the one d,(except it is longer and is provided with a shoulder, y, arranged tooverlap the end of G,) is secured in a like manner to the other end ofthe flask, and thus the bar Gr is held in place by the screws c c beingforced down against the copes or covers C G, which they also hold inplace. This end piece f I denominate the trigger, and its operation Iwill presently describe.

' seen at Fig. 3, so that when the trigger fis knocked off the fIaskwill drop down on the frame F, while the end of the copes remaining onthe In pouring the iiuid steel the steps is slightly lifted up, allowingthe thick side of the casting to be rst exposed to the action of theair. The flask is allowed tov remain thus for about ten minutes so as tocool off, when it can be opened and the castings removed.

I have found from experience that thin castings are less likely to crackwhen the ask is turned up in a vertical position for pouring and .thenreturned to a horizontal position for a definite space of time beforeopening the copes. The reason appears to be that the lines ofcontraction change With the changed positions of the flask.

In other Words, I have found it advisable and important to alter theposition of the flask prior to final cooling.

Having described the apparatus, I will noW describe the process formolding steel castings.`

The mold in the sand having been designed, I

place at such points as experience will suggest` pieces'of copper toserve as conductors of heat, while the interposed sandthat is, thatwhich is between the copper and thev casting-allows the contraction ofthe latter Without crac-king, thus embodying the important features ofboth a copper and a sand mold without the ill ei'ects exy perienced ineach by itself. y

I am aware that pieces of iron have been placed in sand-molds Where ironcastings are to be made for the purpose of chilling the casting, but theobject of the. copper in my process is for an en` I entirely overcome byslightly displacingl the copper cope just sufficient to remove it fromits original bed b y a sliding movement, thereby loosing it from thecasting Without opening` the ask 5 and it may be entirely opened, ashereinbefore set forth.

I am familiar With the patent granted to F. F. Smith November 20, 1864,for castingploW-points, and do not wish to be understood as claiminganything containedtherein;l but Having described the apparatus andprocess, what I claim as new, and desire to secure by Letters Patent, is

1. The process herein described of preventing cracking, porosity, orother defects in steel castings by the employment of copper or itsequivalent in a mold of sand, substantially asv herein set forth.

`the castings,A will be thrown forward and thusy free the casting frombinding.

4. I also claim in the apparatus the combination and arrangement of theflask with the floorframe, the copes, the clamp-bar, set-screws, andtrigger, all constructed substantially as described, for the purposesset forth.

Witness my hand and seal this 12th day of September, 1871.

WM. KELLY. [L. s.]i

Witnesses:

A. I. MOXHAM,

W. P. COLEMAN.

2. I also claim pouring duid steel into a mold

